Quinine(cinchonan-9-ol, 6′-methoxy-, (8α,9R)—) is an antiprotozoal and an antimyotonic, and is known for the treatment of malaria caused by Plasmodium species, the treatment of nocturnal recumbency leg muscle cramps, and the treatment of babesiosis caused by Babesia microti. 
Various salts of quinine are known including quinine hydrochloride, and quinine sulfate. Crystalline quinine sulfate is known to exhibit low solubility in water at room temperature.
Different crystalline forms, non-crystalline forms, hydrates and solvates of an active agent can exhibit vastly different physical properties such as solubility, melting point, hardness, optical properties, dissolution, and the like. These differences such as varying dissolution can result in differences in the therapeutic activity. A thorough understanding of the various crystalline forms, non-crystalline forms, hydrates and solvates of an active agent is an important consideration in formulating the active agent, specifically when trying to achieve consistency of any resulting pharmaceutical product batch to batch.
There remains a need in the art for new solid forms of quinine having improved properties of solubility, stability, processability and the like.